Cleaner what a great step in the right direction for tracking down thiefs and griefers however it does no good if they people already put there items inside chests. What our/my server is looking for is a chest tracker/logger. For a few purposes, first to track the location of all placed chests. Second to log the contents of all chests to the extent that it can be accessed from outside the game or inside. Basically along the lines of the /preview feature in cleaner but give each chest an ID # when its placed and have a master chest that if you typed in something like /preview chest 1 then right click the master chest it would show everything in it. And for the command just like cleaner be permission based.
My plugin does most of this for chests, furnaces and crafting benches But, im not finished yet so i could add more, however logging contents of chests and how users changed chests is not possible at the moment. It produces a text file on the server only admins can see.. Click on the link in my signature to find out more